If you clear both hobj1 and hobj2, then there are no references to the object. MATLAB destroys the
object and frees the memory used by that object.
Deleting Handle Objects
To remove an object referenced by any number of handles, use delete. Given hobj1 and hobj2,
which both refer to the same object, delete either handle. MATLAB deletes the object:
hobj1 = HdClass(8);
hobj2 = hobj1;
delete(hobj1)
hobj2
hobj2 =
handle to deleted HdClass
Use clear to remove the variable from the workspace.
Modifying Objects
When you pass an object to a function, MATLAB passes a copy of the object into the function
workspace. If the function modifies the object, MATLAB modifies only the copy of the object that is in
the function workspace. The differences in copy behavior between handle and value classes are
important in such cases:
• Value object — The function must return the modified copy of the object. To modify the object in
the caller’s workspace, assign the function output to a variable of the same name
• Handle object — The copy in the function workspace refers to the same object. Therefore, the
function does not have to return the modified copy.
Testing for Handle or Value Class
To determine if an object is a handle object, use the isa function. If obj is an object of some class,
this statement determines if obj is a handle:
isa(obj,'handle')
For example, the containers.Map class creates a handle object:
hobj = containers.Map({'Red Sox','Yankees'},{'Boston','New York'});
isa(hobj,'handle')
ans =
1
hobj is also a containers.Map object:
isa(hobj,'containers.Map')
ans =
1
Querying the class of hobj shows that it is a containers.Map object:
class(hobj)
Object Behavior
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